What Do Hormones Have to Do with Aging? What Does Aging Have to Do with Hormones?

1. What Do Hormones Have to Do with Aging? What Does Aging Have to Do with Hormones? Director and President Kronos Longevity Research Institute (KLRI) Phoenix, Arizona S. Mitchell Harman, M.D., Ph.D.

2. A Definition of Aging? • The related deterioration of physiological functions necessary for : • Fertility • Survival • Progressive loss of: • Reserve capacity of organ systems • Ability to compensate for stress or injury • Process terminating inevitably in death of the organism • Increased susceptibility to age-related disease • Death from disease, not “old age”

3. Theories of Aging • Genetic • Aging is “programmed” into the genes • Certain genes are “timekeepers” for the aging process • Wear and Tear • Cumulative damage to cells from • Metabolic processes • Environmental factors • Mechanisms to resist and repair damage are critical

4. oxygen glucose Antioxidants (GSH, tocopherols, etc.) N O2radicals DNA damage Protein damage Lipid damage O• Energy (ATP) SOD Cell Membrane Mitochondria OH- Cytoplasm -proteins H2O2 Catalase GPX H2O + O2 Defense Enzymes Repair Processes Nucleus (DNA) Cellular Damage and Defense N

5. Age-related Changes in Body Composition and Function • Body Composition • Loss of lean body (muscle) mass • Decreased strength • Decreased fitness and loss of functional capacity • Increase in total fat mass (percent body fat) • Insulin resistance (type 2 diabetes) • Increased LDL cholesterol, triglycerides, and fatty acids • Decreased bone density (negative calcium balance) • Metabolic/Physiologic Function • Decreased protein synthesis • Slower healing • Reduced immune system function • Altered hormone balance

6. Age-related Changes in Body Composition in Normal Sedentary Men Muscle Mass (lbs) 70 Fat (%) 60 50 Body Composition 40 30 20 10 20 30 40 50 60 70 80 Age (years) (Balagopal et al. Endocrine 7:57, 1997)

7. Decreases in Muscle Strength with Age Men 250 Women 200 Isokinetic Force (Nm) 150 100 10 20 30 40 50 60 70 80 Age (years) (Borges, Scand J Rehabil Med 21:45, 1989)

8. Age-Related Declines in VO2maxin Sedentary and Physically Active Individuals 70 men Sedentary women 40 yr Longitudinal 50 yr Longitudinal 60 60 yr Longitudinal 70 yr Longitudinal 50 VO2 MAX (ml/kg/min) 40 30 20 10 40 50 60 70 80 90 Age (years) (Wiswell et al., J Gerontol 56:M618, 2001)

9. What Are Hormones? • Natural chemical regulators of cell physiology • Secreted into the blood by specialized glands and act at a distance on one or more target organs • Mechanisms of Action • Peptides/Proteins: act at cell membrane receptors • Steroids: enter nucleus and regulate genes

10. Hypothalamus Releasing Factors Pituitary Liver Thyroid anterior posterior Trophic Hormones - GH TSH IGF-I Adrenal LH FSH Fat ACTH Cartilage - Testis Bone Gonads Peripheral Hormones Ovary Muscle SUMMARY OF HORMONE PHYSIOLOGY Higher Centers Neural activity (neurotransmitters) - + +

11. How Do Hormones Change with Normal Aging? • Estrogens- decrease to very low levels over a 1-3 year period at menopause (between ages 45-55) • Testosterone (T)- Gradual decline from age 30 onward reaching low (hypogonadal) levels in >50% of men by age 65 • Growth Hormone (GH)- Gradual decrease in secretion (and circulating IGF-I levels) from age 45-90 • Adrenal Steroids- • Active adrenal hormones (cortisol and aldosterone) change little • DHEA, steady decrease with age to very low levels in both sexes • Thyroid- not much change in healthy men and women, but increased prevalence of hypothyroid disease in older persons. • Insulin- loss of sensitivity to insulin action with aging and obesity

12. Linear Segment Plots by Decade; Longitudinal Effects of Aging on Date-adjusted T and Free T Index 0.6 20 (177) (177) 0.5 18 (144) (151) Total Testosterone (nMol/L) 0.4 16 (144) Free T Index (nMol/nMol) (151) (158) 14 (109) 0.3 (158) (109) (43) 12 (43) 0.2 10 50 30 40 60 80 70 90 50 30 40 60 80 70 90 Age (years) Age (years) (Harman et al. J Clin Endocrinol Metab 86:724, 2001)

13. Percentage of Healthy BLSA Men by DecadeHypogonadal by Total T and Free T Criteria 94 100 80 251 Testosterone Free T Index 60 Percentage 350 40 20 332 279 18 201 0 20-29 30-39 40-49 50-59 60-69 70-79 80+ Age Decade (Harman, et al. J Clin Endocrinol Metab 86:724, 2001)

14. Effects of Aging on Growth Hormone Secretion in Men 15 Young 10 5 0 Growth Hormone (ng/ml) 8:00 am 12:00 pm 4:00 pm 8:00 pm 12:00 am 4:00 am 8:00 am Time (Corpas, et al., J Clin Endocrinol Metab 75:530, 1992)

15. Serum IGF-I Levels vs. Age in Healthy Women and Men in the BLSA 500 (n=131) (n=258) Women Men 400 r = 0.546 p < 0.0001 r = 0.639 p < 0.001 300 IGF-I (ng/ml) 200 100 0 20 40 60 80 100 20 40 60 80 100 Age (years) (O’Connor, et al. J Gerontol 53:M176, 1998)

16. Similarities of Changes in Body Composition, Muscle Strength, Aerobic Capacity and Metabolic Variables with Aging and in Hormone Deficiency/Excess States High Cortisol Low T Low E2 Low GH Aging Lean Body Mass Muscle Strength Aerobic Capacity Percent Body Fat Total and LDL Cholesterol Insulin sensitivity Glucose tolerance

17. Relationship of Aging Process to Hormone Regulation? Underlying Aging Processes Oxidative Stress? Glycosylation/Crosslinking? Other? ? Altered Hormone (1) Secretion (2) Action Damage to DNA, Lipids, Proteins Altered Cellular Function ? Aging Changes: Body Composition Function

18. Strategies for Intervention • Replace hormones

19. Study Design - Subjects and Interventions Subjects: Healthy women and men, ages 65-88 y (mean, 72 y) with baseline age-related reductions in serum IGF-I (<230 µg/L) and low to low normal gonadal steroid levels (women had had no exogenous estrogens for at least 3 months; men had total T levels ≤16.3 nM/L [470 ng/dL]). Study Design: Double-masked, placebo-controlled, randomized, non cross-over, 2x2 factorial Women Men GH + HRT Placebo GH + T Placebo GH Placebo + HRT GH Placebo + T GH + HRT GH + T GH Placebo + HRT Placebo GH Placebo + T Placebo GH = rhGH 20 µg/kg s.c. 3x/wk in the p.m. HRT = 100 µg/day E2 patch + 2.5 mg/day MPA p.o. T = 100 mg Testosterone enanthate i.m. every 2 wk (Blackman et al., JAMA 288:2282, 2003)

20. Hormone Levels in Men Before and During Treatment IGF-I (ng/ml) (Blackman et al., JAMA 288:2282, 2003)

21. 12 LBM 10 8 0.0001 6 0.0001 4 2 0.059 0 Placebo T GH GH+T Effects of Hormone Administration on Lean Body Mass and Body Fat (DEXA) in Healthy Elderly Men 5 0 0.12 -5 Percent Change -10 0.0001 -15 0.0001 Fat Mass -20 -25 Placebo T GH GH+T GROUP (Blackman et al., JAMA 288:2282, 2003)

22. 10 Strength 8 6 0.053 4 0.28 2 0.86 0 -2 -4 Placebo T GH GH+T Effects of Hormones on Strength and VO2max (ml O2/min/kg BW) in Healthy Elderly Men 15 Aerobic Capacity 10 0.0001 5 Percent Change 0.49 0.49 0 0.11 0.11 -5 -10 Placebo T GH GH+T GROUP (Blackman et al., JAMA 288:2282, 2003)

23. Testosterone Prostate Hyperplasia (BPH) Cancer Coronary Heart Disease Decreased HDL Increased LDL Polycythemia Minor Acne Sleep apnea Growth Hormone Arthritis Carpal tunnel syndrome Fluid retention Hypertension Diabetes Cancers (?) Accelerated Aging (?) Female HRT Mastodynia Vaginal Bleeding Thrombosis Cholelithiasis Breast Cancer Potential Risks of Hormone Treatments

24. Frequency of Adverse Effects During Hormone Administration in Healthy Elderly Men Edema Carpal Tunnel Placebo Adverse Effect T Arthralgias GH GH+T Gynecomastia Headaches Men 0 10 20 30 40 50 60 Percent of Group (Blackman et al., JAMA 288:2282, 2003)

25. Strategies for Intervention • Replace Hormones • Replace Cells

26. EDS EDS Selective Destruction and Regrowth of Leydig Cells in Young and Old Rats Young Leydig Cells New Generation of Leydig Cells ? Aged Leydig Cells Adapted from Zirkin, B. et al.

27. Testosterone Secretion by Perfused Testis Before and After EDS Treatment ND ND Adapted from Zirkin, B. et al.

28. Strategies for Intervention • Replace Hormones • Replace Cells • Prevent Damage to Cells

29. Strategies for Intervention • Replace Hormones • Replace Cells • Prevent Damage to Cells • Repair Damage to Cells

30. How Do Hormones Work? Hormone Hormone Receptor Outer Cell Membrane Inner Inactive Enzyme Protein ATP

31. How Do Hormones Work? Binding Outer Cell Membrane Inner

32. How Do Hormones Work? Change in Receptor Configuration Outer Cell Membrane Receptor Activation Inner

33. How Do Hormones Work? Outer Cell Membrane Inner Lysis of ATP

34. How Do Hormones Work? Outer Cell Membrane Inner ADP

35. How Do Hormones Work? Outer Cell Membrane Inner Phosphorylation

36. How Do Hormones Work? Outer Cell Membrane Inner Enzyme Activation

37. Why is Hormone Regulation and Action Altered in the Elderly? Hormone Hormone Receptor Outer Old Cell Membrane Inner Inactive Enzyme Protein ATP

38. Why is Hormone Regulation and Action Altered in the Elderly? Binding Outer Old Cell Membrane Inner

39. Why is Hormone Regulation and Action Altered in the Elderly? No Change in Receptor Configuration Outer Old Cell Membrane No Receptor Activation Inner Enzyme Protein Remains Inactive

40. Effects of Saturated vs. Polyunsaturated Fat on Stimulated Cylase Activity in Hepatocytes and Adipocytes of Old Rats 10% Corn Oil 1000 10% Coconut Oil 8.5% Coco/2.5% corn 800 Adenyl Cyclase Activity (pmol/mg/10 min) 300 600 200 400 100 200 Hepatocytes Adipocytes 0 7 6 5 4 9 8 7 6 5 4 -log [Glucagon] M -log [Isoproteronol] M From: Dax et al. Endocrinology, 1990, 127:2236

41. KLRI Omega-3 Hormone Pilot Study • Six men and six women > 60 years of age • Dietary Intervention • Non oily fish x 6/week plus 15 ml/day olive/corn oil (50/50) • Oily fish x 8/week plus 15 ml/day fish oil (4 g of Ω-3) • Provocative Testing of Multiple Hormone Axes • Pituitary: GnRH and GHRH tests • Adrenal: ACTH test • Testis: hCG stimulation (men only) • Liver: glucagon stimulation test • Fat cells (catecholaminergic): graded isuprel test • Insulin sensitivity: statin-insulin suppression test • Results?? (study complete, assays pending)

42. Summary • Biological aging in humans produces changes in • Hormone secretion and action • Body composition and function • Some (but not all) aging changes in body composition and function are attributable to hormonal alterations • Potential sites of intervention include • Hormone replacement • Cellular processes of oxidation and glycosylation • Cell membrane signal transduction • Stem cells • More research is needed!